Ristretto shots (literally restricted) can be used as the basis for many other drinks but also work quite well when drunk as an Espresso shot.
Here are the methods and tips on making a good Ristretto shot.
Use 12 grams of ground coffee per Ristretto shot.
Ristretto Grind: Ultra Fine
Method: Extraction with hot water under very high pressure. A fast short extraction is the key here using about half to three quarters of the water of an Espresso shot. Tamp the coffee really firmly to maximise the extraction if an ultra fine grind is not available.
Duration: Extract just 1 to 1.5 ounces per shot under high pressure. Extraction time is shorter than an espresso and uses less water.
Crema should be golden brown with a sweet taste. The shot produced will be a less bitter than an Espresso shot, verging on almost sweet for a dark roast, and it has quite a strong body with chocolaty aftertaste.
Serve: In a regular cup and top up with hot water and or milk to make an Americano or stronger Latte coffee. Add micro foamed milk to create a Cortado or an awesomely smooth tasting Flat white.